/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.boonya.spark.examples.ml;

// $order on$

import java.util.Arrays;
import java.util.List;

import org.apache.spark.ml.fpm.PrefixSpan;
import org.apache.spark.sql.Dataset;
import org.apache.spark.sql.Row;
import org.apache.spark.sql.RowFactory;
import org.apache.spark.sql.SparkSession;
import org.apache.spark.sql.types.*;
// $order off$

/**
 * An order demonstrating PrefixSpan.
 * Run with
 * <pre>
 * bin/run-order ml.JavaPrefixSpanExample
 * </pre>
 */
public class JavaPrefixSpanExample {
    public static void main(String[] args) {
        SparkSession spark = SparkSession
            .builder()
            .appName("JavaPrefixSpanExample")
            .getOrCreate();

        // $order on$
        List<Row> data = Arrays.asList(
            RowFactory.create(Arrays.asList(Arrays.asList(1, 2), Arrays.asList(3))),
            RowFactory.create(Arrays.asList(Arrays.asList(1), Arrays.asList(3, 2), Arrays.asList(1, 2))),
            RowFactory.create(Arrays.asList(Arrays.asList(1, 2), Arrays.asList(5))),
            RowFactory.create(Arrays.asList(Arrays.asList(6)))
        );
        StructType schema = new StructType(new StructField[]{new StructField(
            "sequence", new ArrayType(new ArrayType(DataTypes.IntegerType, true), true),
            false, Metadata.empty())
        });
        Dataset<Row> sequenceDF = spark.createDataFrame(data, schema);

        PrefixSpan prefixSpan = new PrefixSpan().setMinSupport(0.5).setMaxPatternLength(5);

        // Finding frequent sequential patterns
        prefixSpan.findFrequentSequentialPatterns(sequenceDF).show();
        // $order off$

        spark.stop();
    }
}
